An optical mount is an optomechanical device that supports an optical element so as to ensure that the specifications of the optical element are not unintentionally compromised. As researchers and product developers push the boundaries of the optical sciences, there has been an increasing need for optomechanical assemblies that more fully preserve the specifications of the high performance optical elements they support. Many modern optical mounts significantly compromise the specifications of the mounted optics.
Laser quality optical elements are typically finished to very high tolerances. For example, a laser quality mirror would typically be polished flat to within 0.063 μm to 0.032 μm, or about 1/10 to 1/20 of the wavelength of red light emitted from a HeNe laser. Currently available optical mounts have been found to exert forces on the precision optics that substantially degrade their optical performance, thereby degrading the performance of the optical system in which they are being used. For example, the flatness of a laser mirror is degraded by securing it with a nylon tipped set screw driven into the optic's edge. Another example being the optical retardation of a half wave plate used to control the polarization of a light field has its polarization properties compromised when mounted in a traditional mount.
Many existing devices contain, for example, individual spring-loaded fingers to clamp the optic, each requiring individual adjustment and creating unbalanced forces of different magnitude and direction. The designs have many parts and are difficult to adjust without creating unexpected forces and stresses. Existing devices often are not adaptable for different sized optics, because, for example, spring forces are not easily adjustable.
In addition to maintaining the specifications of the mounted optics, there are advantages to maintaining access to as much of the front surface and perimeter of an optic as possible.